Light-emitting device and surface light source

Abstract

A light-emitting device includes a support including a wall portion; a light-emitting element placed on the support and surrounded by the wall portion in a plan view; a first light-transmissive member having a first outer surface and a second outer surface, which is located above the first outer surface and is located inside the first outer surface in the plan view, and covering the light-emitting element and the wall portion; and a light-shielding member covering the first light-transmissive member. The first outer surface and the second outer surface are exposed from the light-shielding member, and a surface roughness of the first outer surface is rougher than a surface roughness of the second outer surface.

1 . A light-emitting device comprising:
 a support comprising a wall portion;   a light-emitting element located on the support and surrounded by the wall portion in a plan view;   a first light-transmissive member having a first outer surface and a second outer surface and covering the light-emitting element and the wall portion, the second outer surface located above the first outer surface and located inside the first outer surface in the plan view; and   a light-shielding member covering the first light-transmissive member, wherein:   the first outer surface and the second outer surface are exposed from the light-shielding member, and   a surface roughness of the first outer surface is greater than a surface roughness of the second outer surface.   
     
     
         2 . The light-emitting device according to  claim 1 , wherein an arithmetic average roughness of the first outer surface is in a range from 1.2 times to 5 times an arithmetic average roughness of the second outer surface. 
     
     
         3 . The light-emitting device according to  claim 1 , wherein the arithmetic average roughness of the first outer surface is in a range from 100 nm to 500 nm. 
     
     
         4 . The light-emitting device according to  claim 1 , wherein the arithmetic average roughness of the second outer surface is in a range from 50 nm to 200 nm. 
     
     
         5 . The light-emitting device according to  claim 1 , wherein in a cross-sectional view, an upper surface of the wall portion has an inclined surface inclined downwardly toward an outside. 
     
     
         6 . (canceled) 
     
     
         7 . The light-emitting device according to  claim 1 , wherein a first angle formed by the first outer surface and a lower surface of the support is less than a second angle formed by the second outer surface and the lower surface of the support. 
     
     
         8 . The light-emitting device according to  claim 1 , wherein the first outer surface and an outer surface of the wall portion are flush with each other. 
     
     
         9 . The light-emitting device according to  claim 1 , wherein:
 an upper surface of the first light-transmissive member defines a recess, and   the light-shielding member is disposed in the recess.   
     
     
         10 . The light-emitting device according to  claim 1 , wherein in the cross-sectional view, the light-shielding member has a first side inclined outwardly toward a top. 
     
     
         11 . The light-emitting device according to  claim 1 , further comprising:
 a second light-transmissive member surrounded by the wall portion and covering the light-emitting element, wherein:   in the cross-sectional view, the light-shielding member has a second side and a third side, the second side facing the light-emitting element, the third side located opposite to the second side, and   in the cross-sectional view, a length of the second light-transmissive member in a lateral direction is greater than a length of the second side in the lateral direction and is less than a length of the third side in the lateral direction.   
     
     
         12 . The light-emitting device according to  claim 11 , wherein in the plan view, the second light-transmissive member overlaps an entirety of the light-shielding member. 
     
     
         13 . The light-emitting device according to  claim 1 , wherein in the plan view, the light-emitting element overlaps an entirety of the light-shielding member. 
     
     
         14 . A planar light source comprising:
 a plurality of the light-emitting devices according to  claim 1 ;   a substrate where the plurality of the light-emitting devices are disposed; and   at least one partition member disposed on the substrate, wherein:   the at least one partition member comprises:
 a plurality of first partition wall portions each comprising a first ridge line extending in a first direction; and 
 a plurality of second partition wall portions, each comprising a second ridge line extending in a second direction intersecting the first direction, 
   in a plan view, a plurality of partitioned regions each surrounded by the first ridge line and the second ridge line, are disposed in the first direction and the second direction, and   each of the plurality of the light-emitting devices is disposed in a corresponding one of the plurality of partitioned regions.   
     
     
         15 . The planar light source according to  claim 14 , wherein:
 the plurality of the light-emitting devices comprise a first light-emitting device and a second light-emitting device disposed side by side in the second direction,   the first partition wall portion comprises a first partition lateral wall and a second partition lateral wall disposed across the first ridge line,   in the plan view, the first partition lateral wall is located between the first light-emitting device and the first ridge line,   the first partition lateral wall is inclined at an inclination angle α greater than 0° and less than 90° with respect to a lower surface of the substrate, and   when a length in the second direction from a center of the first light-emitting device to a center of the second light-emitting device is set as W1 and a length of the first partition wall portion in a third direction orthogonal to the first direction and the second direction is set as W2, the inclination angle α satisfies a relationship of 2×arctan(2×W2/W1)<α<3×arctan(2×W2/W1).   
     
     
         16 . The planar light source according to  claim 15 , wherein the length in the second direction from the center of the first light-emitting device to the center of the second light-emitting device is in a range from 8 mm to 18 mm. 
     
     
         17 . The planar light source according to  claim 15 , wherein a length of the first partition wall portion in the third direction is in a range from 0.2 times to 0.3 times the length in the second direction from the center of the first light-emitting device to the center of the second light-emitting device. 
     
     
         18 . A light-emitting device comprising:
 a support comprising a wall portion;   a light-emitting element located on the support and surrounded by the wall portion in a plan view;   a first light-transmissive member having a first outer surface and a second outer surface and covering the light-emitting element and the wall portion, the second outer surface located above the first outer surface and located inside the first outer surface in the plan view; and   a light-shielding member covering the first light-transmissive member, wherein:   in a cross-sectional view, an upper surface of the wall portion has an inclined surface inclined downwardly toward an outside.   
     
     
         19 . The light-emitting device according to  claim 18 , wherein a first angle formed by the first outer surface and a lower surface of the support is less than a second angle formed by the second outer surface and the lower surface of the support. 
     
     
         20 . The light-emitting device according to  claim 18 , wherein the first outer surface and an outer surface of the wall portion are flush with each other. 
     
     
         21 . A planar light source comprising:
 a plurality of the light-emitting devices according to  claim 18 ;   a substrate where the plurality of the light-emitting devices are disposed; and   at least one partition member disposed on the substrate, wherein:   the at least one partition member comprises:
 a plurality of first partition wall portions each comprising a first ridge line extending in a first direction; and 
 a plurality of second partition wall portions, each comprising a second ridge line extending in a second direction intersecting the first direction, 
   in a plan view, a plurality of partitioned regions, each surrounded by the first ridge line and the second ridge line, are disposed in the first direction and the second direction, and   each of the plurality of the light-emitting devices is disposed in a corresponding one of the plurality of partitioned regions.